physical education. n. (Education) training and practice in sports, gymnastics, etc, as in schools and colleges. Abbreviation: PE. physâ²ical educaâ²tion. n. instruction in sports, exercise, and hygiene, esp. as part of a school or college program.
3. Stress/injury. Stress on the tissues or any type of injury in the mouth can cause canker sores. Since the sores are actually tiny ulcers, they can be caused by any kind of hard brushing or eating something that can cause bruises or lead to tissue inflammation in the mouth.
Canker Sores. 1  develop on the soft tissues inside the cheeks or lips, underneath the tongue or at the base of the gums. 2  arenât contagious. 3  are round with a white or yellow center and a red border. 4  generally heal within one to two weeks. 5  caused by immune-suppressing viruses, autoimmune disorders and auto-inflammatory disorders.